The ribosomal aspects of heat injury are the main subject of this grant. A two-fold objective is sought: 1) determination of the configurational modifications and functional fidelity of S50 subunits from heat injured cells and 2) investigation of the mechanisms of assembly, conformation, and functional fidelity of the S30 particles. The techniques involved are in vitro protein synthesis, gel electrophoresis, assays of enzyme function relating to protein synthesis and ultracentrifugation utilizing sucrose density gradients.